Steven T. Moore Thomas Haslwanter Ian S. Curthoys Stuart T. Smith Measurement of Three Dimensional Eye Position using Image Processing: A Geometric Approach. 436-440 1994 conf/icip/1994 ICIP (1) db/conf/icip/icip1994-1.html#MooreHCS94 http://dx.doi.org/10.1109/ICIP.1994.413351